Question

I would like to run the following basic procedure within my Maven 3.0.4 project. I have all the basics in place and haven’t had any issues but am running into problems on step #3. For some reason the basic solution is eluding me, since it seems like something that should be very obvious.

1. Run a basic clean/install (without annotation processing)
2. Request that a site build be run
3. Before the site build kicks off, run annotation processing on the compiled classes using an annotation processor class that was compiled in the initial steps

I tried setting up the annotation processing goal as follows:

<plugin>
  <groupId>org.bsc.maven</groupId>
  <artifactId>maven-processor-plugin</artifactId>
  <executions>
    <execution>
      <id>process</id>
      <goals>
        <goal>process</goal>
      </goals>
      <phase>pre-site</phase>
      <configuration>
        <outputDirectory>${basedir}/target/generated-documentation</outputDirectory>
        <processors>
          <processor>com.mydomain.MyFancyAnnotationProcessor</processor>
        </processors>
      </configuration>
    </execution>
  </executions>
</plugin>

For some reason this doesn’t seem to be working.
I feel like I’m doing something very, very silly that is preventing it from working.

I am using the Maven Annotation Plugin instead of the basic, Mojo Apt Plugin. I don’t mind switching if someone has a working solution with that one. I tried both without any immediate signs of success. Again, it feels like it’s just something obvious that I’m overlooking.

Error received:

[INFO] diagnostic error: Annotation processor 'com.mydomain.MyFancyAnnotationProcessor' not found
[ERROR] error on execute: error during compilation

Answer 1

My guess would be that the plugin is not including the current project itself in its classpath. The best solution would be to separate the annotation processor into its own (sub-)module if possible. If you can’t do that, you may be able to just add this project itself as a dependency of the plugin (using a <dependencies> section under the plugin node).

As a diagnostic note, you can run maven with the ‘-X’ argument to see detailed info about the build. This should show you exactly what is on the classpath when the plugin is executed.